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Should I trade my 2021 Newmar Mountain Aire for a Pre DEF Prevost or Newell?

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RockyDocH

RVF Newbee
Joined
May 2, 2023
Messages
2
Considering trading my 21 Mountain Aire for a pre-DEF Prevost or Newell Coach. Has anyone out there done this? Just looking for some advice.
 
Older coaches have their share of structural, mechanical, fuel system, and house issues as well and once you learn to finer points of caring for, and coping with, modern emissions systems, they become manageable and its easy enough to prevent serious problems.

Right now I’m stranded because of metal fatigue in my CAC (and related problems caused by it) and its only seven years old. And while seven years isn't very old, its old enough that OE parts are no longer available and there are exactly two after market coolers available - neither closer than three to five days by truck freight. So while there are pros and cons to both, I can’t logically conclude that older is better.

When I was having emissions problems (as I learned about the systems and how to live with them) I considered a very nice 2009 500hp Monaco Bishop IV. Sometimes I wish I’d made the change but chances are I would be just as vulnerable to becoming stranded for non-emissions related issues, exactly as I am now.

Having gained an understanding of modern emissions and especially with the advent of the DSS (DEF Sensor Simulator) I’d opt for newer rather than older at this point. Also your emissions system is under warranty for 5 years/100,000 miles - don’t ever let anyone tell you different. And if you do have emissions issues there is a lot of information available on the forums to help get you through.

This is just my .02 worth and I’m feeling a little negative right now, going on a week in a hotel waiting for parts and losing my slot at the service center (and spending every bit of my Mothership budget on unexpected repairs) but I’ve spent a lot of time thinking about both sides of this issue, and frankly at this point I’m leaning towards neither. Hopefully that will change by the end of the week.
 
There is always a chance that other states follow California in banning older diesels. There maybe an exemption for RV today, but try to read the regulations and explain them to a CHP on the side of the road as they impound your “no compliant” diesel rig.

 
As a former Newmar owner (2x) and now have a Prevost I wholeheartedly agree what @Rich W. says in his post above about learning and caring.

My first question would be what are you hoping to achieve by changing? Are you hoping to avoid the def sensor issue that has plagued others?

Getting into a Prevost or Newell can be a big jump as they are a lot to get your hands around learning how the engineering and the design works. If and that’s a big IF the coach has been well maintained with good records and transparency about any issues that persists then venture cautiously.

Sadly I know a few Prevost owners with pre-def coaches who have headaches on their hands and contemplating getting out because of cost and time. There is no perfect solution and there are pluses and minuses on both.
 
I’ll weigh in as a former Dutch Star owner who jumped into a 2015 Newell. It’s been an awesome experience in more ways than we have room on this post.

Do I hate the DEF system? Yup…haven’t met anyone who doesn’t. It’s a system that’s just not as refined as autos…frustratingly.

I think there are 3 general types of Newell owners…if that's at all possible to say:
-Those who have unlimited funds and will simply have Newell fix anything, or even just trade in every couple years.
-Those who are mechanically inclined and can take on anything but leave the big stuff for Newell and/or Cummins.
-Those who are true “backyard mechanics” who enjoy keeping or restoring an older Newell. NewellGurus is chocked full of this talent!

The fourth, if there is one, that “SOME” would claim shouldn’t have ANY RV…let alone a custom coach…is the person who doesn’t fit into any of the above, doesn’t care, and doesn't stress about problems or breakdowns.

That was a total mind-ramble…sorry if it makes zero sense. I just think getting into an older Newell is full of challenges; I have a handful of friends who are, and all of them are mechanical and continually fixing or working on their coaches. Half of them have DEF like mine, yet none of the problems have anything to do with their DEF.

THAT SAID…I just got through a DPF code issue that ended up being a CAC boot. So, it really had NOTHING to do with the DEF system, even though the code was a “DPF” code.

I sure hope this helps…way longer that I expected to to be. But, I guess it’s because this is such a personal question to answer shortly.
 
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I like what @CaptainGizmo wrote and that applies to Prevost too. One other thing I’ll add in that pertains to Prevost. Your current coach has an interior design that’s probably modem and you like it. When you go back into earlier vintages that interior might be very dated and some might describe as hideous. So if the DW has any say you might he looking at a remodel which can be expensive. Additionally many converters use crestron and if it’s old you will want to upgrade to current iPad tech. That’s expensive too. There are people out there with pre def buses that like them just how they are and just want the Prevost characteristics.
 
My recommendation is, unless you really want a Prevost, don't do it.

The depreciation hit on the MA will be significant. Financing (if needed), on a greater than 10 year old coach won't be found at favorable rates/terms. The interior of an old coach will be very dated and in need of updates ($$$). Some maintenance items on a Prevost can also be crazy expensive.

If just running away from potential diesel exhaust fluid (DEF) or diesel particulate filter (DPF), just keep in mind that those that don't have issues, don't usually post on forums that the systems run without issues. Those that have problems do post and therefore skew the view.

To close on a positive note, I see many pristine looking Prevost coaches on our travels. One in particular belongs to a fellow dog show participant and I've seen the coach over many years. It's a non-slide coach and he is very proud of his machine and should be.
 
I would be far more inclined to delete the factory emissions on the current coach than step back in time with an older one.
That would turn the MA into a unicorn you could not legally sell. Also, if you break down on the road, good luck finding a shop that will work on a deleted unit. Very stiff monetary fines for the shop.
 
The delete need not be permanent, keep the trouble prone beta testing emissions stuff boxed up and bolt it back up when ready to sell. It only takes about a half an hour with an F-250 - 450 with the 6.7L diesel.
 

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